TSUKUBA, JAPAN. There is ample evidence that any procedure involving damage to the myocardium (middle muscular layer of the heart wall) results in an inflammatory response. Thus, catheter ablation is associated with post-procedure inflammation. Since there is a close relationship between inflammation and atrial fibrillation (AF), it is reasonable to pose the question – Would attenuating or eliminating the post-PVI inflammation result in greater freedom from AF recurrence? A group of physicians from the University of Tsukuba now report the results of a study designed to provide an answer to this question.

A total of 125 paroxysmal afibbers with no underlying structural heart disease with an average age of 61 years (80% male) and an average duration of AF of seven years underwent a pulmonary vein isolation procedure using the double Lasso technique. Linear lesions were added as needed and all patients were also ablated to prevent right atrial flutter (cavotricuspid ablation). Upon completion of the procedure, the study participants were randomized into two groups. The corticosteroid group had a saline hydrocortisone solution administered intravenously immediately after the procedure and then received oral prednisone (0.5 mg/kg/day) for the following three days. The control (placebo) group received a saline solution administered intravenously immediately after the procedure and then received a placebo (lactose) orally for the next three days.

During the first month following the procedure, 27% of the members of the corticosteroid group experienced AF recurrence of which 7% occurred within the first four days (immediate recurrence), and the remaining 20% occurred between four and thirty days after the procedure (early recurrence). In the control group, 49% experienced recurrence within the first month with 31% being immediate and 18% being early. Thus, the incidence of immediate recurrence was substantially less in the corticosteroid group.

Fourteen months after the PVI, 85% of the members of the corticosteroid group were afib-free without the use of antiarrhythmics as compared to 71% in the placebo group. The Japanese researchers also made the following interesting observations:

• A high body temperature and an elevated level of the inflammatory marker, C-reactive protein (CRP), were significantly associated with an increased risk of experiencing immediate, but no early recurrence.
• Frequent ectopics (premature atrial complexes or PACs) and episodes of non-sustained AF were associated with an increased risk of experiencing early, but not immediate recurrence.

The researchers conclude that post-procedure corticosteroid therapy decreases the recurrence risk at 14 months by preventing immediate AF recurrence caused by inflammatory responses. They suggest that the transient use of small amounts of corticosteroids shortly after a PVI procedure may be effective in preventing both immediate and medium term (14 months) AF recurrences.

Koyama, T, et al. Prevention of atrial fibrillation recurrence with corticosteroids after radiofrequency catheter ablation. Journal of the American College of Cardiology, Vol. 56, No. 18, October 26, 2010, pp. 1463-72

Editor's comment: The 85% recurrence-free rate at 14 months (no antiarrhythmics) experienced by patients assigned to the corticosteroid group is indeed impressive considering that repeat ablations were not allowed in the study. It would thus seem that reducing post-procedure inflammatory response is an important part of ensuring long-term success. Hopefully, this approach to inflammation control will become standard practice, but until it does, natural anti-inflammatories may be helpful. For further information on this see Post Ablation Care protocol.